Dr. Teemu Öhman

Visiting Scientist
USRA - Lunar and Planetary Institute

From 2010 to 2013 I was a postdoctoral fellow at the LPI, working mostly with Dr. David Kring and Dr. Patrick McGovern. My work focused on lunar impact cratering using a multitude of remote sensing datasets, as well as the tectonic evolution of Alba Mons volcano on Mars. Particularly during the Alba Mons’ circumferential graben project I created and analyzed a large amount of high-resolution digital elevation models (DEMs) from stereo imagery. I also wrote a hands-on beginner’s guide about processing and analyzing DEMs with USGS ISIS, NASA Ames stereo pipeline, and ESRI’s ArcGIS, which might be useful for those wishing to create planetary DEMs for themselves. Other community assets I was priviliged to work with include the lunar crater 3D models, and the revised lunar impact crater database providing useful scaling equations for lunar cratering studies.

Before joining the ranks of LPI postdocs, I finished my PhD studies at the Department of Geosciences, University of Oulu, Finland, in 2009. My PhD thesis dealt with the interaction of the impact cratering process and pre-existing tectonic structures in the target rocks on Mars, Venus, and the Moon. The distinctly square-shaped Meteor (aka Barringer) Crater in Arizona is a classic example of a crater where target fractures have controlled the final shape of the crater (for a short comparison between Meteor Crater and other polygonal impact craters, see pp. 81–86 in the Lunar Analogue Training guidebook).

My passion for impact cratering on the Earth and other terrestrial planets was initiated in the University of Oulu already during my MSc project. My MSc thesis dealt with the geology and shock metamorphism of Saarijärvi impact structure in northern Finland – a topic to which I returned while at the LPI. In addition to Saarijärvi, I have studied a number of other Finnish and Fennoscandian impact structures, with emphasis on Söderfjärden and Lappajärvi. The more exotic locations where my impact cratering research has taken me include the giant Popigai and Kara impact structures in arctic Russia.

Since August 2013 I have been a no-cost visiting scientist at LPI. My current projects include, for example, dating the Söderfjärden impact event, further research on the interplay between impact cratering and tectonics on Venus, the Moon and Mars, and petrophysics of Kara impactites. A new, challenging but extremely exciting venture deals with promoting (geo)tourism and research of the Finnish impact structures.